大气气溶胶吸湿性及其对环境的影响

Atmospheric Aerosol Hygroscopicity and Their Influence on Environment

吸湿性是气溶胶重要的物理化学特性,不仅会影响气溶胶的生命周期和大气行为,还会对大气环境、气候和人体健康产生重要影响。本文简要介绍了气溶胶吸湿参数和热力学模型,对粒径、化学组分以及多组分共存等因素对气溶胶吸湿性的影响进行分析,进一步总结了城市、农村森林和海洋极地等不同区域气溶胶吸湿观测结果。吸湿增长因子g(RH)、散射吸湿增长因子f(RH)和吸湿性参数κ等常用吸湿参数可以衡量气溶胶的吸湿能力;Zdanovskii-Stokes-Robinson(ZSR)混合定律和各种热力学模型能预测不同化学成分气溶胶的吸湿能力,是研究多组分混合气溶胶和气相平衡的重要工具。粒径、化学组分和混合状态影响气溶胶的吸湿性,如气溶胶g(RH)、潮解点或风化点的改变。由于排放源和环境条件的不同,城市、农村、森林、海洋、极地地区气溶胶粒径分布、化学组分和混合状态具有差异,气溶胶吸湿性不同。气溶胶吸湿性直接影响气溶胶含水量和相态,改变气溶胶的大气化学过程、老化过程和大气寿命,还影响环境能见度、辐射效应和在人体内的沉积位置和毒性。通过总结吸湿参数、理论模型、实验室研究、外场观测和环境影响等多方面的最新研究成果,以期为未来的吸湿研究提供参考和借鉴。

Hygroscopicity is one of the aerosol’s most important physicochemical properties,which affects the lifetime and atmospheric behavior of aerosols.It plays a vital role in the environment,climate change,and human health.The hygroscopicity parameters and thermodynamic models are introduced.The effects of aerosol diameter,chemical composition,and multi-component aerosol on hygroscopicity are analyzed in the following section.The relevant observations in the urban,rural area,forest,polar region,and ocean are summarized.Hygroscopicity growth factor(g(RH)),scattering enhancement factors(f(RH))and hygroscopicity parameterκare common hygroscopicity parameters which can represent aerosol hygroscopicity.The Zdanovski-Stokes-Robinson(ZSR)mixing rule and many thermodynamic models can predict the aerosol hygroscopicity with different chemical compositions,which are some important tools to study the multi-component aerosol and phase equilibrium.Aerosol diameter,chemical composition and mixed state affect hygroscopicity,for example g(RH),and changes in deliquescence relative humidity or efflorescence relative humidity.Because of different emission sources and environmental conditions,the aerosol particle size distribution,chemical composition and mixed state are different in the urban area,rural area,forest,polar region and ocean,and then aerosol hygroscopicity are different.Hygroscopicity affects aerosol water content and phase state directly,and atmospheric chemical processes,aging process and lifetime of aerosol will be changed.Environmental visibility,radiation effects,and aerosol deposition sites and toxicity in the human body also are influenced by aerosol hygroscopicity.Overall,a comprehensive review of hygroscopicity parameters,theoretical models,laboratory studies,field experiments,and environmental impacts provides a reference for future research.